Mortise lock



` ug., 7, w23..- www3 J. E'. WORT MORTISE Ifcx vFiled Aug.' 1'7. 192x Patented ug. 7, 1923.

unirse sierras JOHANNES EI-IRHORN HJ'ORT, 0F COPENHAGEN, DENMARK. i

MORTISE LOCK.

`Application ledAugust 17, 1921. Serial No. 492,965,

T 0 all Lo/wm t may concern.'

Be it known that I, JOHANNES EHRHORN l-lJon'r, subject of King of Denmark, residing at Copenhagen, Denmark, have invented certain new and useful Improvements in Mortise Locks, of which the following is a specification.

The invention relates to aI mortise bolt lock with tumblers and a very compact lock casing adapted to be inserted in a small round hole bored into the door to be locked, inste-ad of as heretofore into a long mortised hole.

The invention differs from the known lock of this kind by its special shape of lock casing, so that the corresponding hole in the door, into which the lock is inserted, weakens the door as little as possible. Furthermore, the look constructed according to the invention is characterized by the bolt-tail being disposed in the central plane of the lock, so that the key-bit will only need'one projection in order to move the bolt, even if the key has to be inserted from either side of the lock. Finally, according' to the invention, all the tumblers are pivoted at one end about a pin at the end farthest from the face plate, and are engaged by the key-bit about half way between the said pivot and the tumblerhead. This feature necessitates the individual steps in the key bit corresponding to the individual tumblers to be shaped very accurately with the proper projection, as any error will be nearly doubled at the tumbler-head, and the lock will thereby become more difficult to pick.

@n the drawing, which illustrates one construction of the invention,

l Fig. 1 shows the lock in side elevation, with the cover removed,

Fig. 2 the same in top view, and

Fig. 3 the same viewed from the rear end.

1 is the so-called face plate which by means of screws or the like fastens the lock in position, 2 is the lock-casing shaped as a cylinder with two flat segmental faces parallel to the bolt e. The bolt 3 is centrally disposed in the lock-casing and is fitted with an inwardly directed extension 4 located in the same plane as the bolt and fitted with two guiding lugs 5 and 5, which are guided in corresponding recesses 6 and 6 provided in the two cylindrical walls of the lock-casing 2, midway between its two plane walls.

7 is the key hole and 8 a recess in the bolt correspondingto the key, the said recess being engaged by the central projection of the key-bit, which thus moves the bolt, when the key is being turned. 9 is one of the tumblers which are pivoted, at their inner ends about a pin 10 and each of which supports, at its outer end, a flat spring 14 resting against a stud 15. Hereby the specially shaped heads 11 of the tumblers are pushed, in known manner, beyond one of two lugs 12 and 12 provided on the bolt 3, 4, in such a manner that the bolt cannot be moved until all the tumblers have been lifted, by

the key-bit against the action of the individual springs 14, exactly so far that the heads 11 of the tumblers will allow the two lugs 12 and 12 of the bolt to pass.

The lock casing is most conveniently formed by two symmetrical parts, which are joined by riveting of the studs 10 and 15, or by means of screws 16 passing through the same.

Having now particularly described and ascertained the nature of lmy said invention and in what manner the same is to be performed, I declare that what I claim is 1. A mortise lock, comprising a substantially-cylindrical lock casing, a key-actuated bolt slidable therein and provided at one side with spaced upper and lower laterallyprojecting lugs, and a tumbler pivoted in the casing on the same side of the bolt as the lugs and extending at its free end into the space l between the lugs; said tumbler having a head adjacent its free end yfor cooperation with said lugs and normally engaged with one of them to prevent retraction of the bolt, but adapted to be moved out of such engagement by the action of the key to permit the bolt to 'be retracted, said head having a height such as to enable it to pass through the space between the lugs during the movements of the bolt.

2. A mortise lock, comprising a substantially-cylindrical lock casing, a key-actuated bolt slidable therein and provided at one side with centrally-located, spaced upper and lower laterally-projecting lugs, and provided in advance of said lugs with a longitudinal guide slot, a stud mounted in the casing and extending horizontally through said slot, a tumbler pivoted at its rear end in the casing on the same side of the bolt as said lugs and having its free front end eX- a spring yattached to the front ,fend of ,the tr-aeted.,1said `head having a height s uch as tumbler and engaging said stud; said lkturnto enable it' to Ypass "through `the space be- 10 bler having adjacent its free end 4a head. tween-the lugs during the movements of the which is normally engaged with -the lower zbolt.

5 lug by the pressure of the spring to pre- In testimony whereof have allixed my vent retractionl of the bolt, but adapted to signature, be moved out of such engagement by the ac- L tion'of the key to permit the bolt to be Vre'- JES :EHRHORN HJ ORT. 

